The present invention relates to an apparatus and method for compensating for an output signal, and more particularly, to an apparatus and method for compensating for an output signal, which is capable of maintaining an output signal at a stable value regardless of a supply voltage supplied to an output unit such as a DAC (Digital to Analog Converter).
In general, a semiconductor for sensor receives an external analog signal and converts the received analog signal into a digital signal using an ADC (Analog to Digital Converter). Then, the digital signal is processed through digital signal processing, and the semiconductor for sensor reconverts the digital signal into the analog signal through a DAC.
At this time, the ADC and a digital logic part which performs digital signal processing do not directly receive power from a power supply unit, but receive a preset operating voltage from a regulator. Then, the ADC and the digital logic part perform their roles based on the stable operating voltage.
On the other hand, the DAC directly receives power from the power supply unit, and performs a preset role using the received power.
The related art of the present invention is disclosed in Korean Patent Laid-open Publication No. 2000-0034175 published on Jun. 15, 2000 and entitled “Apparatus for compensating for output signal”.
The DAC of the conventional semiconductor for sensor converts a digital code processed through digital signal processing and outputs an analog signal. The output signal is designed to be proportional to the voltage of supplied power.
Thus, when power supplied to the DAC fluctuates, the output signal of the DAC also fluctuates.
For example, when the supplied power is reduced by 5% in comparison to power supplied in a normal situation, the output of the DAC is also reduced by 5%. Such a malfunction may cause a distorted signal output, instead of a normal signal output. Thus, when an ECU receives the output signal, the ECU may make a wrong decision.
Furthermore, when the ECU makes a wrong decision, an actuator which operates according to a command of the ECU may cause a malfunction. In the case of a semiconductor for sensor which is used for a vehicle, a system malfunction may significantly threaten a driver's safety.